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Retirement

Solo 401(k) Calculator

Calculate how much you can contribute to a solo 401(k) as both employee and employer.

Updated June 2026 · Editorial standards

Your details

$
$
%
Total annual contribution
$41,470
Projected balance
$1,819,089
Employer portion (20% of net SE)
$18,470
Total growth
$989,689

As both employee and employer, you can contribute $41,470/year to your Solo 401(k) — increase to $30,500 employee deferral at age 50.Employee: $23,000 · Employer: $18,470 · Over 20 years: $1,819,089 projected.

Contribution breakdown

Employee deferral$23,000
Catch-up contribution (age 50+)$0
Employer contribution (20% of net SE)$18,470
Total contribution (IRS cap: $69,000)$41,470
Projected balance$1,819,089
By the KalkWise Editorial Team Reviewed for accuracy Updated June 2026

What is the solo 401(k) calculator?

In short

A Solo 401(k) allows self-employed individuals to contribute up to $69,000 in 2024 ($76,500 with catch-up at 50+). This combines an employee deferral of up to $23,000 plus an employer contribution of up to 20% of net self-employment income.

Calculates the maximum Solo 401(k) contribution — combining employee deferrals, catch-up contributions, and employer profit-sharing — and projects the retirement balance.

How to use this calculator

  1. 1Enter your gross self-employment income.
  2. 2Enter your age — those 50+ qualify for an additional $7,500 catch-up contribution.
  3. 3Enter your desired employee deferral amount (up to $23,000, or $30,500 at 50+).
  4. 4Set years to retirement and expected return to see your projected balance.

The formula

Er=netSE×20%
T=min(Ee+CU+Er,$69,000+CU)
FV=T×(1+r)n−1r×(1+r)
T = min(Ee + CU + Er, 69000 + CU); FV = T × ((1+r)^n − 1) / r × (1+r)
Ee
— Employee deferral (up to $23,000 + catch-up)
Er
— Employer contribution = net SE income × 20%
CU
— Catch-up = $7,500 if age ≥ 50
T
— Total = min(Ee + CU + Er, $69,000 + CU)
FV
— Future value of T over n years at rate r

Worked example

The scenario

$100,000 income, age 45, $23,000 employee deferral, 20 years, 7% return.

gives

The result

Employer contribution: ~$18,470. Total: $41,470/year. Projected: ~$1.7M.

Common use cases

  • Self-employed individuals maximizing tax-deferred retirement savings.
  • Freelancers comparing Solo 401(k) vs SEP-IRA contribution limits.
  • Business owners age 50+ taking advantage of catch-up contributions.

Limitations & assumptions

  • Requires filing Form 5500 annually once plan assets exceed $250,000.
  • Employee deferrals must be elected by December 31 (unlike SEP-IRA contributions).
  • Cannot contribute as employer if net SE income after deductions is zero.

Frequently asked questions

The total limit is $69,000 ($76,500 with catch-up). This combines a $23,000 employee deferral ($30,500 at 50+) plus up to 20% of net SE income as the employer contribution.

Disclaimer: KalkWise calculators are provided for general informational and educational purposes only and do not constitute financial, investment, tax, or legal advice. Results are estimates based on the figures you enter and the assumptions described above. Actual outcomes will vary. Consult a qualified professional before making financial decisions.